Two young women were backpacking in Vietnam together while on break from their jobs in South Korea where they were teaching English. Karin Bowerman, 27, and Cathy Huynh, 26, during what was supposed to be a fun-filled adventure in Vietnam were admitted to Khanh Hoa General Hospital in the beach town of Nha Trang. Both young women were having trouble breathing and were vomiting.

Huynh was released from the hospital initially but Bowerman passed away just three hours after being admitted due to respiratory failure. Two days later, Huynh passed away.

Authorities still don't know the true cause of their deaths. World Health Organization suspects poison is to blame but finding where the poison came from has proven difficult.

Bowerman and Huynh's deaths are two of a few different mysterious deaths that have occurred in South East Asia. International media linked these deaths to an incident in Thailand in June, where two Canadian sisters passed away. Noemi and Audrey Belanger, 25, and 20, were found dead in their hotel room covered in vomit. In Feburary 2011, New Zealander Sarah Carter, 23, died in Chiang Mai, Thailand after being admitted into a hospital for similar symptoms as Bowerman and Huynh.

Bowerman's items were shipped back to Lake Geneva, Wisconsin where she grew up and fundraisers helped the more than $10,000 worth of costs the family had to pay to get her cremated body back to Wisconsin.

Huynh from Hamilton, Ontario was a seasoned traveler. Her high school friend Jetty Ly told CNN, "I encouraged her to follow her dreams, go where her heart wants to go. I wanted to live vicariously through her adventures. But not like this."

There have been no firm answers to what caused the death of these girls and the young travelers before them. According to CNN In 2011 TV3 went to Chiang Mai, Thailand to investigate the death of Sarah Carter. Show producers talked to Dr. Ron McDowall a United Nations toxic chemical consultant, who looked at Carter's pathology reports and he beliebed that she died of pesticide ingestion.

CNN reported that traces of chlorpyrifos were found in the Downtown Inn. Chlorpyrifos can cause symptoms such as dizziness, nausea and in high levels, respitory paralysis and death. The chemical is banned in the U.S for use in hotels and homes but is still legal in Thailand and Vietnam.

However, even if Chlorpyrifos is the culprit, it is extremely hard to verify. It passes in about one day so it is difficult to identify. Vietnamese authorities have released limited information about the young girls and their untimely deaths.

Autopsy results come back in a few weeks times which means they could have more answers.

On a tribute to the girls on the Groove Korea website, friends have poured in with comments about the two. A friend of Bowerman

Deanne Colbert said on the website,"Any time it came to doing something new, I can hear her say so clearly, 'I'm not afraid' (from a popular Eminem song). She was such a strong woman, the most amazing friend anyone could ever have. I speak for all our friends in saying that our hearts are truly broken for the loss of our lovely Kari. We will never forget! Saranghae forever Kari!"

Sophia Hoang said of Cathy Huynh on the Groove Korea website,"Cathy was always full of life, love and joy. Just her smile and the sound of her laughter alone would enlighten any room. She is unquestionably the definition of a forever friend; always there to listen, to laugh with, to enjoy the simplest things in life with. Forever friends are hard to find, difficult to leave and never forgotten. Cathy will never be forgotten and will remain forever in our hearts."